Intermittent and uncontrollable electric power generators (“Intermittent Generators”) are commonly used to generate electric power. For example, power may be produced utilizing wind turbine generators with electrical output which is a function primarily of wind velocity and duration, but may be affected by a number of other variables. A significant characteristic from the standpoint of scheduling and dispatching energy from this type of resource is that the resource's ability to generate electricity is variable and intermittent depending upon weather circumstances beyond the administrator's control. There are other types of intermittent or “as-available” power generators, including but not limited to solar power, wave power, and geothermal power, all of which depend upon forces of nature beyond the administrator's control. Another example of an intermittent or “as-available” generator is a cogenerator or qualifying facility which has its net electrical output affected by changes in steam demand, host electrical load changes, and other “behind the fence” influences and actions which are beyond the administrator's control or prediction. Since substantial power is produced by such facilities, it is desirable that they be integrated into the power grid so that the power they produce can displace power generated by less economic resources or less environmentally friendly resources. Electricity produced by more conventionally powered and controllable generators is generally more readily predictable and controllable than the power delivered by an Intermittent Generator. It is highly desirable that an accurate estimate, or schedule, of the power to be generated by the Intermittent Generator be determined and continuously updated with the grid controller to support the reliable operation of the electric power grid, and to minimize economic and compliance penalties which may arise from large deviations between the actual electric output of an Intermittent Generator and its scheduled, or estimated, output maintained with the grid controller. This permits the grid controller to more reliably and economically match generation to load, and be able to take into account likely available intermittent sources of electric generation, resulting in increasing the ability to displace energy produced by less economic or less environmentally friendly generation sources with energy produced by more environmentally friendly or economical intermittent resources.
In spite of significant resources and efforts being expended to enhance the accuracy of forecasting the electrical output of wind powered electrical generators, and other Intermittent Generators, it continues to be extremely difficult to provide accurate and up-to-date estimates of the production of electricity from these facilities.
Actual electrical generation which is less than the quantity of energy scheduled (estimated) with the grid controller causes the need for certain adjustments in the amounts of electricity supplied to the grid. Of even greater consequence, at least to the Intermittent Generator, is the delivery of more electricity than scheduled (estimated) with the grid controller. When this occurs, the grid controller routinely assesses economic and compliance penalties against the intermittent generation facilities for the delivery of greater amounts of electricity than previously scheduled (estimated) to the grid controller.
Accordingly, it is highly desirable that a method be available for the administration of wind powered and other Intermittent Generators, so that the administrator of such generation can be able to schedule, or estimate, their production of electricity in such a manner as to minimize the difference between the electric power schedules submitted to the grid controller, and actual electric power generation produced in real time.
Typically the administrator of a generation plant provides a schedule, or estimate, of projected electric generation to the grid controller at various times, typically from one hour to one or more days in advance of the period of actual power production. The estimate may be adjusted to account for expected changes in the forecasted power production, according to a defined notice period. For example, a grid controller may require receipt of a revised schedule of power production as much as two hours prior to the time interval affected by the revised schedule. Such revisions to the schedule of power production may also apply to the remaining time period for which the grid controller allows or requires changes.
Accordingly, methods have been sought to schedule, or estimate, the amount of power which will be produced by wind powered or other Intermittent Generators as accurately as possible in order to minimize the differences between the scheduled energy output and the actual amount of power produced, on an updated basis, and to timely provide updated estimates to the grid controller.